Mathematics · 2023
JEE Main · 15 April 2023, Shift 1 · Q19
The mean and standard deviation of 10 observations are 20 and 8 respectively. Later on, it was observed that one observation was recorded as 50…
The mean and standard deviation of $\displaystyle 10$ observations are $\displaystyle 20$ and $\displaystyle 8$ respectively. Later on, it was observed that one observation was recorded as $\displaystyle 50$ instead of 40. Then the correct variance is
Official answer
From NTA’s final answer key for this paper.
(3)
$\displaystyle 13$
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JEE Main 2023 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.